JPS60104455A - Safety control valfe for operating fluid system - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to safety control valves for fluid system operation, and more particularly to non-pryable safety control valves for fail-safe braking systems.

Many large vehicles, especially ground vehicles, employ fail-safe brake systems that employ spring braking and fluid pressure release. In the event of a fluid pressure system failure, the brakes are automatically applied and the vehicle cannot be moved until an auxiliary pressure source is available to release the brakes.

Some types of motor vehicles are equipped with auxiliary devices that require the operator to move the vehicle for a short period of time or simply operate an auxiliary valve in order to continue driving. . This equipment allows vehicles to be moved if necessary for repairs or similar work. One problem with this equipment is that rough acts can open the auxiliary valve and move the vehicle or drain the auxiliary supply.

The main objective of the present invention is to solve the problems of the prior art mentioned above.

Another object of the invention is to provide a non-unlockable safety control valve for a fail-safe motor vehicle brake system. Still another object of the invention is to provide a non-unlockable safety control valve for a fail-safe motor vehicle brake system. According to the present invention, the above-mentioned object is to provide a safety control valve including a valve body to an inner valve body, and a valve body mounted in the valve body such that it can freely reciprocate, and a communicating position and a non-communicating position. a control valve that is movable between positions and controls fluid communication from a fluid source, the control valve having opposite ends of the valve spool protruding from the valve body; and a bracket, the bracket being connected to the valve body. a chain operative to engage opposite ends of the valve spool and held in a fixed position to prevent movement of the valve spool from the selected one of the communicating and non-communicating positions; This is achieved by providing a safety control valve for operating a fluid system characterized in that it includes a locking device.

The above objects and advantages of the present invention, as well as other objects and advantages, will become apparent from the following description with reference to the accompanying drawings.

Referring to the accompanying drawings, and in particular to FIG. 1, there is shown a brake control device of the type having a plurality of fail-safe brake mechanisms 10 as a fluid system, the brake mechanisms having springs and fluid pressure. is of the type that is released. Such braking devices are well known and are employed primarily on large heavy vehicles, and they also include sufficient capacity within the control device to operatively lock and release the brakes of the wheels of the vehicle. It is a mechanism that prevents movement unless brake or control pressure is applied.

Such devices are typically 'Fail Safe 1
Known as a type brake system, it normally acts to automatically apply the brakes to the vehicle to stop the vehicle even if the control pressure inside the system is removed. The apparatus has a main fluid pressure source 12 connected by a suitable conduit 14 to a master control valve 16 which directs fluid through a conduit 18 and a branch 20.22 to control the braking mechanism. 10 in a controllable manner. The main fluid pressure source 1
2 may be any suitable source such as a transmission control fluid;
Alternatively, it may be a tool control and energizing fluid.

An auxiliary control system is provided to provide additional pressurized fluid to control the brake system if the main system fails. The auxiliary device is used to enable the vehicle to be moved for maintenance or inspection or to move the vehicle to a safe location in the event of a main system failure.

The auxiliary device according to the invention includes a suitable secondary or auxiliary fluid pressure source 24, and the fluid is supplied through a suitable conduit 26 to a suitable valve device 28, which is connected to a delay cylinder device 30. It may also be a pneumatically actuated valve or cylinder that actuates or energizes the cylinder device. The auxiliary fluid pressure source 24 may be any suitable fluid source, such as a vehicle air source having a storage tank for holding and supplying air to operate the auxiliary control device.

Cylinder 30 operably supplies pressurized oil or hydraulic fluid through conduit 32 to an auxiliary control valve or diverter valve 34 which operatively controls communication with main control valve 16 through conduit 36.

The auxiliary control valve 34 is configured as a safety control valve. That is, the auxiliary control valve 34 is reciprocatably mounted inside a valve body or housing 37 having a cavity (not shown) therein to control communication between the conduits 32 and 36. and a valve spool 38. The valve spool 38 may be of any suitable construction to define a two-position valve, providing a communicating position and a non-communicating position. Here, these two positions correspond to both left and right end positions of the movement of the valve spool 38. Both ends of the spool 38 project from the housing, and a stop ring 40 is disposed at the tip of each end to define the end positions of the valve spool's travel.

The valve 34 is provided with a suitable locking device in the form of a bracket 42, which bracket is the valve block.

- a pair of upright portions 4 operatively engaged with opposite ends of the rod 38;
It has a U-shape with a diameter of 4.46. The bracket 42, in each described embodiment, includes:
A pair of grooves 48 and 50 are installed directly below the valve 34.
and a pair of cap screws 52, 54 are engaged in the grooves. The base of the bracket does not necessarily need to be fastened under the base of the valve body, but may be fastened to one side of the base of the valve body or to the top thereof. The locking bracket does not necessarily require both legs, but can function with a single blocking member if it is desired to lock the valve in a single position. The cap screw 52.54 and groove 48.50 cooperate to define the outermost position of the valve spool 38.
, 54, when tightened with a suitable wrench, the valve 34
Thus, for example, when the bracket is moved to the rightmost position as shown in FIG.
8 is similarly moved to its rightmost position to establish a non-communicating position. In this position, the cap screws 52,54 may be tightened to essentially lock the valve in the non-communicating position. It is therefore necessary to have a wrench capable of loosening the screws 52, 54 in order to move the valve 34 into the operating position and thereby to be able to remove the pulley and move the car. Will.

The operating or communication position of the valve 34 is defined as the left end position as shown by the phantom line in FIG.

Therefore, with valve 34 in the rightmost or blocked position, there is little risk of automatic, accidental, or malicious operation of the auxiliary device.

This safety control valve related to the diverter valve can also be applied to devices other than brake devices. For example, it may be applied to a fuel system to prevent the engine from starting. It could also be applied to hydraulic control systems for tools and the like so that the tools are not operated under certain conditions.

Other applications include, for example, a device for alternately selecting one of two attachments for a single control valve circuit.

It can thus be seen from the foregoing that there is provided a safety control valve for the operation of fluid systems that is inherently non-lockable. It will be appreciated that many changes and modifications may be made without departing from the spirit and scope of the invention as defined in the claims.

[Brief explanation of the drawing]

FIG. 1 is a schematic diagram of a brake control device implementing the present invention;
FIG. 2 is a side view of a preferred embodiment of the safety control valve according to the present invention. In the figure, 12...Main fluid pressure source 16...Main control valve 24...Auxiliary fluid pressure source 34...Auxiliary control valve (safety control valve) 38...Valve spool 42...Bracket Yes agent Asamura Ko 48504

Claims (1)

[Scope of Claims] A valve body, and a valve spool that is reciprocatably mounted within the valve body and is movable between a communicating position and a non-communicating position to control communication of fluid from a fluid source. a control valve, wherein both ends of the valve spool protrude from the valve body; and a bracket, the bracket operative to engage the ends of the valve spool and held in a fixed position to control the valve body. A locking device for preventing movement of the valve spool from a selected one of the communicating position and the non-communicating position.